Position sensors of a position tracking system may be mounted on various medical devices for tracking the position of the medical device in a patient body.
For example, U.S. Pat. No. 5,803,089, whose disclosure is incorporated herein by reference, describes a system for monitoring the position of a medical instrument with respect to a patient's body and for displaying at least one of a plurality of prerecorded images of said body responsive to the position of said medical instrument. A field generator may be associated with one of the units for generating a position characteristic field in an area including the target operation site. One or more field sensors may be associated with either of the units responsive to the presence of the position characteristic field for producing one or more sensor output signals representative of said sensed field.
U.S. Pat. No. 6,434,507, whose disclosure is incorporated herein by reference, describes an apparatus that comprises a tool body and tool attachment onto which emitters are fixedly mounted. At least one tool tip is coupled with the tool body in a removable manner. An electrical sensor is positioned to be operated when the tool tip is changed either by coupling the tip to or removing the tip from the tool body.